This proposal focuses on the inhibition of degradation of abnormal proteins by T4 bacteriophages and on the relationships between the E. coli Rho protein, cellular proteolytic activities, and effector molecules such as guanosine tetraphosphate (ppGpp). Genetic, recomvinant DNA techniques will be utilized to determine the gene(s) of phage T4 that function to inhibit abnormal protein degradation in host E. coli cells. Bacterial mutants that either hyper- or hypodegrade abnormal proteins have been found and characterized as E. coli rho mutants. The Rho protein possesses NTPase and transcription termination activities. Studies are proposed to determine whether rho mutants show altered patterns of protein degradation due to defects in transcription termination or to other functions of the Rho protein. Since the rho mutants display abnormally low levels of ppGpp under certain conditions of altered protein degradation, genetic techniques will be used to raise and to lower ppGpp levels in the rho mutants. Thus, we shall determine whether ppGpp levels are responsible for the altered patterns of protein degradation.